Phoenix Logs/Banished Units/Locust
From Halopedia, the Halo wiki
Locust walkers are siege vehicles armed with an unstable focus cannon that deals continuous damage to buildings and vehicles. Locusts are fitted with energy shields but are relatively fragile once those shields are depleted.
One of the many Covenant vehicles modified by the Banished to serve their needs, the Locust is a walker unit originally built for mining and excavation purposes. The Covenant repurposed Locusts to demolish enemy buildings and outposts with sustained bombardment from their focus cannons, but the Banished have managed to make these vehicles even more dangerous than they were before.